[Platelets play pivotal role in the pathophysiology of unstable angina, acute myocardial infarction and in complications following percutaneous coronary intervention. Three classes of platelet-inhibiting drugs, aspirin, thienopyridines and platelet glycoprotein IIb/IIIa inhibitors are now commonly used for the prevention and treatment of the disorders of coronary artery thrombosis. For the last several decades, aspirin has been the sole option for antiplatelet therapy in the treatment and prevention of the manifestations of cardiovascular disease. However, a wider selection of antiplatelet agents, including the thienopyridines (ticlopidine and clopidogrel) and the platelet glycoprotein IIb/IIIa receptor antagonists are available today. This review summarizes these drugs and scientific data that have led to their use in primary and secundary prevention, unstable angina, myocardial infarction and percutaneous coronary intervention.]

[Acetylsalicylic acid effectively blocks the activation of platelets, and becomes a basic element of antithrombotic therapy of patients with high cardiovascular risk. Decrease of platelet reactivity is due to the irreversible inhibition of COX- 1 isoenzime in platelets during treatment. Choosing the right dose is still not an easy task. Bleeding side effects are frequently seen in patients treated with this drug worldwide. Clinical benefit does not improves with escalated doses (300 mg), however the risk of haemorrhagic events increases. Therefore acetylsalicylic acid dose should be reduced to the effective minimal dose (75-150 mg daily) after the acute phase of atherothrombosis in order to prevent side effects. Effect of acetylsalicylic acid differs individually, it might be important screening out those patients who respond less to the drug. Resistance is still an evolving field, proper methodology is to be determined. Right indications of acetylsalicylic acid needs balance between reaching clinical benefit and avoiding side effects. The Hungarian Cardiovascular Therapeutic Consensus Conference 2009 suggested acetylsalicylic acid in primary prevention for those males only, who have overt cardiovascular risk, and SCORE result is more than 10%, with no gastrointestinal haemorrhage in medical history, and with a well-controlled hypertension. Lifelong aspirin prevention should be used after all diagnosed cardiovascular atherothrombotic event as a cornerstone of secondary prevention with low dose (75-150 mg daily) in both genders.]

[The acetylsalicylic acid (ASA) is one of the oldest and most widely used drugs in the world. Currently, it is the most commonly used for the treatment and prophylaxis of cardiovascular diseases. Today, there has been consensus that the risk of ASA’s side effects in primary prevention is greater than the expected benefits. However, it maintains its leading role in the secondary prevention of cardiovascular diseases. There is also a consensus that small doses are recommended for preventive purposes, but there is no agreement whether it should be 75 or 81 or 100 mg. The authors summa­rize the publications published in this topic. ]

[Nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most widely used drugs worldwide. Gastroduodenal ulcers are found at endoscopy in 15 to 30% of patients who use NSAIDs regularly. The annual incidence of severe upper gastrointestinal complications such as bleeding or perforation is 1.0 to 1.5%. From a cost-benefit perspective, prevention strategies should consider both gastrointestinal, and recently, cardiovascular risk factors. No prophylaxis is necessary with low gastrointestinal risk. There are currently four possible strategies to reduce the risk of adverse gastrointestinal effects: 1. the use of selective COX-2 inhibitors or coxibs rather than traditional NSAIDs; 2. cotherapy, primarily with proton pump inhibitors, to ensure protection to gastric mucous membrane; 3. co-therapy with a coxib and a proton pump inhibitor in patients with very high risk (eg., history of bleeding); 4. eradication of Helicobacter pylori infection in patients with a history of ulcer. The use of coxibs decrease the risk of gastrointestinal damage by roughly 50%. In the presence of gastrointestinal risk factors or for patients on aspirin also treated with an NSAID or a coxib, protection with a proton pump inhibitor is recommended. Proton pump inhibitor therapy is also useful for the prevention and treatment of NSAID-induced dyspepsia. The beneficial effects of proton pump inhibitors cannot solely be explained by their profound antisecretory action. Therefore, several acid secretion- independent mechanisms of action have been proposed.]

[Patients with diabetes mellitus have an increased risk of cardiovascular events and this risk is often present in the prediabetic phase of the type 2 diabetes. Diabetic patients have altered platelet function, including increased production of thombox ane resulting in increased platelet aggregation. This effect is reversed by aspirin within few days after beginning treatment with 75 mg aspirin daily. These findings of primary and secondary prevention trials in men and women with dia betes mellitus support the view that low-dose aspirin therapy should be used as secondary prevention when not contraindicated, and it should also be used as primary prevention in patients who are at high risk for cardiovascular events. ]